1. Field of the Invention
The present invention relates to optical disk driving apparatuses and methods, and recording media and programs used therewith. In particular, the present invention relates to an optical disk driving apparatus and method for identifying the format of an optical disk loaded into the optical disk driving apparatus, and to a recording medium and program used with the apparatus and method.
2. Description of the Related Art
Presently, multi-disk recorders and players capable of recording on or playing back optical disks having various types of formats have come into common use. In particular, regarding DVDs (digital versatile disks), a plurality of formats capable of recording are used, such as DVD-RAM (digital versatile disk random access memory), DVD-R (digital versatile disk recordable), DVD-RW (digital versatile disk rewritable (common name of re-recordable DVD disks)), DVD+R, and DVD+RW. Accordingly, a disk format must be properly identified for recording or playback.
For example, Japanese Unexamined Patent Application Publication No. 2003-16641 discloses a technology using an optical disk identifying means. The optical disk identifying means changes the rotational speed of a disk to that obtained under spindle control at constant linear velocity, and measures the difference in frequency between a wobble signal frequency and wobble-signal central frequency extracted under spindle control at the constant linear velocity. When the difference in frequency is less than a threshold value, the optical disk identifying means determines that the disk is recordable. When the difference in frequency is greater than the threshold value, the optical disk identifying means determines that the disk is of a playback-only type.
In addition, when a disk format is identified by comparing only the wobble signal frequency and the threshold value, the disk format may fail to be identified.